*{
	margin: 0px;
	padding: 0px;
}
.tou{
	margin: auto;
	width: 900px;
}
.tou ul li{
	float: left;
	list-style: none;
	width: 100px;
	height: 50px;
	background-color: aqua;
	text-align: center;
	line-height: 50px;
}
.tou ul li a{
	text-decoration: none;
	display: block;
	width: 100px;
	height: 50px;
	color: red;
	background-color: gold;
}
.tou ul li a:hover{
	background-color: green;
	color: red;
}